(a) Field of the Invention
The present invention relates to invisible zipper and, more particularly, to a bottom open-end type invisible zipper, which has movable bottom-end piece that can be moved away from the stitching area when using a sewing machine to stitch the zipper to an object.
(b) Description of the Prior Art
A regular bottom open-end type invisible zipper (see FIG. 1) is generally comprised of two zipper tapes 10, two series of teeth 20, two plug members 30, and a bottom-end piece 40. The two series of teeth 20 and the two plug members 30 are respectively fixedly fastened to the zipper tapes 10. The bottom-end piece 40 is fixedly fastened to one plug member 30. This structure of bottom open-end type invisible zipper is suitable for use to close/open an opening in a dress, jacket, etc. When closing, the other plug member is inserted into the bottom-end piece 40, and then the slide is pulled upwards to interlock the two series of teeth. However, because the dimension of the bottom-end piece 40 is much greater than the cross section of the series of teeth 20, the presser foot 100 of the sewing machine cannot pass over the bottom-end piece when fastening the zipper tapes 10 to a dress or the like (see FIG. 2). In order to eliminate the aforesaid problem, an invisible zipper with detachable bottom-end piece is disclosed. According to this design, one plug member 30 is constructed having a split hook 301, and the bottom-end piece 40 is made having hooked portions 402 disposed in one insertion hole 401 for engagement with the split hook 301 after insertion of the plug member 30 into the insertion hole 401. The bottom-end piece 40 is separated from the corresponding plug member 30 before fastening the zipper tapes 10 to the dress or the like. After installation of the invisible zipper, the bottom-end piece 40 is secured to the split hook 301 of the plug member 30. Because the plug member 30 and the bottom-end piece 40 are small elements, it is complicated to form the designed split hook 301 on the plug member 30 and the designed hooked portions 402 in the bottom-end piece 40. Any small error during die-casting or injection molding procedure causes a defective product. Further, because the bottom-end piece 40 is kept separated from the invisible zipper when selling, it tends to be missed.
The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide a bottom open-end type invisible zipper, which has a movable bottom-end piece that does not hinder the stitching operation to fasten the invisible zipper to an object. According to one aspect of the present invention, the bottom open-end type invisible zipper comprises a first zipper tape and a second zipper tape, the zipper tapes each having a respective series of teeth longitudinally disposed at an inner side for interlocking; a first plug member and a second plug member respectively fixedly fastened to the zipper tapes and longitudinally connected to one end of the series of teeth at the respective zipper tape; a movable bottom-end piece slidably coupled to the first zipper tape, the movable bottom-end piece having a receiving chamber adapted to receive the first plug member and the second plug member in parallel; and an escape-preventive structure adapted to stop the movable bottom-end piece from falling out of the first zipper tape, the escape-preventive structure including a male locating means fixedly disposed at the first plug member and a female locating means fixedly disposed at the second plug member for engagement with the male locating means to stop the movable bottom-end piece at the first plug member. According to another aspect of the present invention, the first plug member with the first zipper tape and the second plug member with the second zipper tape can be selectively arranged at either side to fit the left-handed user or the right-handed user.